Serum Creatinine Concentration (Mass Concentration)
This test measures the amount of creatinine, a waste product from muscle metabolism, in your blood. It helps assess how well your kidneys are filtering blood.
["Creatinine levels help check kidney function and detect early kidney problems."]
Key facts at a glance
- LOINC
- 49140-7
- Short code
- CALEVG
- Synonyms
- CEV IgG Titr Ser IF
- Category
- chemistry
- Sample
- serum
- Container
- Red-top serum tube or serum separator tube (SST)
- Units
- N/A
- Ref low
- 0
- Ref high
- 1
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- Immunofluorescence (IFA)
- CPT
- 86651
- SNOMED
- 40668006
- Specimen volume
- 1.0 mL serum (minimum 0.5 mL)
- Stability
- Stable at 2-8°C for 7 days; frozen at -20°C or below for long-term storage up to 1 year; avoid repeated freeze-thaw cycles
- Hemolysis max
- 100
- Lipemia max
- 50
- Icterus max
- 20
- TAT
- 24–96 hours
- Order
- routine
Why This Test Matters
Creatinine is a byproduct of muscle breakdown and is normally filtered out by your kidneys. High levels may indicate reduced kidney function, while low levels could suggest dehydration or muscle loss. This test is often used alongside other measures, like blood urea nitrogen (BUN), to evaluate kidney health.
What to Expect Before the Test
No special preparation is needed for this blood test. You may have a small needle inserted into your arm to draw a blood sample. If you’re dehydrated, your doctor might advise drinking extra fluids the day before.
Common Causes of Abnormal Results
High creatinine levels might be due to kidney disease, dehydration, or conditions that increase muscle breakdown (e.g., severe illness). Low levels could result from dehydration, low muscle mass, or certain medications. Always discuss symptoms with your healthcare provider.
What Your Results Mean
Your results will be compared to standard ranges for your age, sex, and overall health. Your doctor will interpret them in the context of your medical history and other tests. If results are outside normal limits, further evaluation may be needed.
Reference range
Negative: <1:10; Positive: ≥1:10 indicates previous exposure or past infection with California encephalitis virus (La Crosse virus). Seroconversion or a four-fold rise in titer between acute and convalescent samples indicates recent or current infection.N/A
No fasting or special preparation required. Acute and convalescent serum samples collected 2-4 weeks apart are recommended for accurate serological diagnosis. Patient should be informed that the test detects antibodies to California encephalitis virus, a mosquito-borne arbovirus that can cause encephalitis, particularly in children.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Creatinine
Frequently asked questions
How often should I get this test?
Can I eat or drink before this test?
What if my results are different from last time?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 15, 2026. · Read our editorial policy